namei: pass the struct path to store the result down into path_lookupat() (625b6d10) · Commits · e / devices / android_kernel_fairphone_FP4

fs/namei.c

+34 −38

Original line number	Diff line number	Diff line
		@@ -2086,8 +2086,8 @@ static inline int lookup_last(struct nameidata *nd)
		}

		/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
		static int path_lookupat(int dfd, const struct filename *name,
		unsigned int flags, struct nameidata *nd)
		static int path_lookupat(int dfd, const struct filename *name, unsigned flags,
		struct nameidata nd, struct path path)
		{
		const char *s = path_init(dfd, name, flags, nd);
		int err;
		@@ -2108,27 +2108,31 @@ static int path_lookupat(int dfd, const struct filename *name,
		if (!err && nd->flags & LOOKUP_DIRECTORY)
		if (!d_can_lookup(nd->path.dentry))
		err = -ENOTDIR;
		if (err)
		if (!err) {
		*path = nd->path;
		nd->path.mnt = NULL;
		nd->path.dentry = NULL;
		}
		terminate_walk(nd);

		path_cleanup(nd);
		return err;
		}

		static int filename_lookup(int dfd, struct filename *name,
		unsigned int flags, struct nameidata *nd)
		static int filename_lookup(int dfd, struct filename *name, unsigned flags,
		struct nameidata nd, struct path path)
		{
		int retval;
		struct nameidata *saved_nd = set_nameidata(nd);

		retval = path_lookupat(dfd, name, flags \| LOOKUP_RCU, nd);
		retval = path_lookupat(dfd, name, flags \| LOOKUP_RCU, nd, path);
		if (unlikely(retval == -ECHILD))
		retval = path_lookupat(dfd, name, flags, nd);
		retval = path_lookupat(dfd, name, flags, nd, path);
		if (unlikely(retval == -ESTALE))
		retval = path_lookupat(dfd, name, flags \| LOOKUP_REVAL, nd);
		retval = path_lookupat(dfd, name, flags \| LOOKUP_REVAL,
		nd, path);

		if (likely(!retval))
		audit_inode(name, nd->path.dentry, flags & LOOKUP_PARENT);
		audit_inode(name, path->dentry, flags & LOOKUP_PARENT);
		restore_nameidata(saved_nd);
		return retval;
		}
		@@ -2209,10 +2213,8 @@ int kern_path(const char name, unsigned int flags, struct path path)
		int res = PTR_ERR(filename);

		if (!IS_ERR(filename)) {
		res = filename_lookup(AT_FDCWD, filename, flags, &nd);
		res = filename_lookup(AT_FDCWD, filename, flags, &nd, path);
		putname(filename);
		if (!res)
		*path = nd.path;
		}
		return res;
		}
		@@ -2241,9 +2243,7 @@ int vfs_path_lookup(struct dentry dentry, struct vfsmount mnt,
		nd.root.dentry = dentry;
		nd.root.mnt = mnt;
		err = filename_lookup(AT_FDCWD, filename,
		flags \| LOOKUP_ROOT, &nd);
		if (!err)
		*path = nd.path;
		flags \| LOOKUP_ROOT, &nd, path);
		putname(filename);
		}
		return err;
		@@ -2311,10 +2311,8 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags,

		BUG_ON(flags & LOOKUP_PARENT);

		err = filename_lookup(dfd, tmp, flags, &nd);
		err = filename_lookup(dfd, tmp, flags, &nd, path);
		putname(tmp);
		if (!err)
		*path = nd.path;
		}
		return err;
		}
		@@ -3261,44 +3259,42 @@ static int do_tmpfile(int dfd, struct filename *pathname,
		struct file file, int opened)
		{
		static const struct qstr name = QSTR_INIT("/", 1);
		struct dentry dentry, child;
		struct dentry *child;
		struct inode *dir;
		struct path path;
		int error = path_lookupat(dfd, pathname,
		flags \| LOOKUP_DIRECTORY, nd);
		flags \| LOOKUP_DIRECTORY, nd, &path);
		if (unlikely(error))
		return error;
		error = mnt_want_write(nd->path.mnt);
		error = mnt_want_write(path.mnt);
		if (unlikely(error))
		goto out;
		dir = path.dentry->d_inode;
		/* we want directory to be writable */
		error = inode_permission(nd->inode, MAY_WRITE \| MAY_EXEC);
		error = inode_permission(dir, MAY_WRITE \| MAY_EXEC);
		if (error)
		goto out2;
		dentry = nd->path.dentry;
		dir = dentry->d_inode;
		if (!dir->i_op->tmpfile) {
		error = -EOPNOTSUPP;
		goto out2;
		}
		child = d_alloc(dentry, &name);
		child = d_alloc(path.dentry, &name);
		if (unlikely(!child)) {
		error = -ENOMEM;
		goto out2;
		}
		nd->flags &= ~LOOKUP_DIRECTORY;
		nd->flags \|= op->intent;
		dput(nd->path.dentry);
		nd->path.dentry = child;
		error = dir->i_op->tmpfile(dir, nd->path.dentry, op->mode);
		dput(path.dentry);
		path.dentry = child;
		error = dir->i_op->tmpfile(dir, child, op->mode);
		if (error)
		goto out2;
		audit_inode(pathname, nd->path.dentry, 0);
		audit_inode(pathname, child, 0);
		/* Don't check for other permissions, the inode was just created */
		error = may_open(&nd->path, MAY_OPEN, op->open_flag);
		error = may_open(&path, MAY_OPEN, op->open_flag);
		if (error)
		goto out2;
		file->f_path.mnt = nd->path.mnt;
		error = finish_open(file, nd->path.dentry, NULL, opened);
		file->f_path.mnt = path.mnt;
		error = finish_open(file, child, NULL, opened);
		if (error)
		goto out2;
		error = open_check_o_direct(file);
		@@ -3311,9 +3307,9 @@ static int do_tmpfile(int dfd, struct filename *pathname,
		spin_unlock(&inode->i_lock);
		}
		out2:
		mnt_drop_write(nd->path.mnt);
		mnt_drop_write(path.mnt);
		out:
		path_put(&nd->path);
		path_put(&path);
		return error;
		}